A Rogues’ Gallery of Garden Villains

Eventually every gardener compiles his or her personal ‘Rogues Gallery’ of garden villains – those plants which have proved themselves to be an unmitigated menace in one way or another. My own garden is no exception, whether a particular villain was in residence when I arrived or whether through sheer stupidity I introduced it myself. Some of my villains will undoubtedly be known to you already, while others may serve as a timely warning if you should ever be tempted to give them entry to your own garden.

HONEYSUCKLE (Lonicera spp.)

This was a case of double stupidity. The east side chain link fence around my backyard was already covered in honeysuckle when I bought the house, but I compounded the fatal error during the first year here by allowing the fragrance to remind me of childhood memories. My friends and I had a favorite summer-evening meeting place at the corner of our street, and the house at that corner was surrounded by a honeysuckle hedge. So of course I decided to go my childhood memories one better by planting additional varieties along the other two fencelines in order to “ring” my backyard with the nostalgic fragrance. Needless to say, once my back was turned on the honeysuckle for a season or two it decided to not only cover the chainlink fence but also make a land grab for the newly made perennial borders immediately in front of it. However the honeysuckle did not gain its new horizontal territory without a fight; it had to contend with another villain, namely

ENGLISH IVY (Hedera helix)

Forget visions of ivy-covered walls – it can cover beds, borders, and lawn just as quickly. I can’t blame myself for planting this, because it was in place already underneath two huge linden trees in the front yard. It was sharing real estate there with pachysandra which at least has the virtue of not being able to climb. The ivy had climbed up the trees to a respectable height, but it was fairly easy to simply cut the vines at ground level and then yank them off the tree trunks. I left the ivy at ground level to duke it out with the pachysandra but there were also small plantings of ivy along some of the backyard fence perimeters. I made a mental note to dig those small plantings out “one of these days” but promptly forgot about it until I realized that the honeysuckle and the ivy had teamed up in an axis-of-evil pairing to smother the perennial borders along the fences. A planting of English ivy alone can be successfully eradicated using Roundup, but of course in a mixed border (which was rapidly becoming a mixture of only two plant species) that’s not an option. The only choice is to cut, pull, and dig by hand. I am sorry to report that the Devilish Duo lasted longer than my arm and back muscles did. Even the daylilies could not successfully get through the suffocating blanket they created. I have a mental picture of the daylilies slowly drowning, not unlike those old horror movies where one of the good guys sinks tragically to his death in a pit of quicksand!

THE SWEETGUM TREE (Liquidambar styraciflua)

Another villain that was here when I arrived. This is one of those plants where one needs to balance the good against the bad. The good is that they have the potential to be one of the most spectacularly colored trees in the world. Notice that I say “potential” and that is because this is by no means a sure thing. At least with a maple tree – whose leaf shape the sweetgum’s resembles – you have a fairly good guarantee of excellent autumn color. There may be some slight variation from one year to the next depending on temperature and rainfall during the summer, but otherwise it’s a pretty sure bet. Not so with the sweetgum, which has a large degree of variability not only from season to season but between one tree and another. A sweetgum with good color can rival any maple tree that you care to set against it, but the odds are fairly even that you could end up with a dud. I moved into my house early in the year and so had a good six months of anticipation to see how much of a “pillar of fire”(which a good sweetgum is often described as) I had inherited along with the house. Let’s just say that it ended up more resembling a candle in the wind. But I made excuses for it, rationalizing that I had only given it one season and after all I had probably disturbed the surface roots by clearing away the grass beneath it and creating a planting bed. The tree was in a corner and seemed to cry out for a planting of daylilies, hostas, and epimediums among other things.

A word to the wise: Do not EVER make the mistake of creating a planting bed anywhere near the Artillery Range of a sweetgum tree. Why? Because of the negative aspect of a sweetgum tree, which is very negative indeed: This tree produces the nastiest fruiting bodies that you will ever encounter.They are called “sweetgum balls” but in fact they look like a miniature version of the business end of a medieval mace. About the size of a golf ball, they are armed in every direction with spines which have the infuriating habit of grabbing everything they encounter. This is one of the plant kingdom’s best imitations of Velcro.

Because they are lightweight, they can be blown a fair distance in all directions from the tree rather than simply falling straight down in accordance with Newton’s Law. But once they come to rest, whether it be on one’s lawn or in nearby planting beds, they are determined to stay there.  If you try to rake them up, one of two things will happen. Actually both of them will happen because there will be so darn many of the miserable things. Some of them will lodge between the tines of your rake while the others will simply refuse to budge until you literally hack at them, cursing inventively all the while, in order to convince them to release their deathgrip on the grass. An alternate method of getting them mobile is to kick them individually with your foot and then rake them up. To add insult to injury, the sweetgum tree sheds these delightful little objects all year long and not just in the winter, although the largest crop is deposited during that season. Because they are hard, they are by no means a lawnmower’s best friend and so they need to be removed before mowing can commence. Trust me, your lawnmower blade has a better chance against a small branch than against these things. By the way, the sweetgum in my yard only somewhat approached pillar-of-fire status one year out of the past 10. Not the greatest track record and certainly not worth all those damn sweetgum balls.

RUBUS CALYCINOIDES ‘EMERALD CARPET’

You may see this perennial described as the ground cover in answer to many prayers. And on paper it does have an impressive list of supposedly positive attributes. It is evergreen; it has small, scalloped, highly textured leaves which are impervious to foot traffic; it has small single pure white flowers in early summer; it is a weed-smotherer par excellence; it will grow in pretty much any soil or sun conditions; it is impervious to pests and diseases; it spreads by runners and thus never needs to be divided. Sounds perfect, doesn’t it? What they don’t tell you is that this plant has territorial ambitions that would make Genghis Khan, Julius Caesar and Alexander the Great look like shy shrinking violets. I had a difficult area along one side of my house wall and thought this would be the perfect solution. That was about five years ago. It behaved itself for about two years and then decided that it was hungry and needed to gobble up everything in its path. And although it is not a climbing plant, its runners began to investigate the underside of my exterior siding.

Another thing that the descriptions don’t tell you is that this plant is an absolute nightmare to remove if/when you want to get rid of it. After several fruitless attempts to cut into the ever spreading original planting which had already swallowed up my nearby Chocolate Garden (more on that in a future post), choked out the daylilies on the other side of the bed and was now invading the lawn, I resorted to chemical warfare. Even so, it took three separate heavy applications of Roundup to kill the surface growth sufficiently to let me cause my arms and back further damage by digging out the now-dead roots a few months later. If you have a few acres that you will never want to plant anything else in for the rest of your natural lifetime AND those of your grandchildren as well, you might risk planting this. (In idle moments I have wondered which plant would win in an invasiveness contest between this and bamboo. I think it would probably be a tossup.)

BISHOP’S WEED (Aegopodium podagraria)

You would think that the hybridizers would know better than to try to create a decorative garden plant from what is essentially a noxious weed. Admittedly, the variegated version of Bishops Weed is an attractive plant, with toothed leaves of clear true green bordered in white and eventually sporting umbels of white flowers resembling a miniature Queen Anne’s Lace. But it shrugs off difficult conditions of soil, light and moisture far too easily to be a safe resident in most gardens. It spreads both by runners and by seed which is always a dangerous combination. Give it a couple of seasons and it will betray the rampant territorial acquisitiveness acquired from its wild parent. Out of morbid curiosity I planted this along with two other supposed “thugs”, Vinca minor and a plain green mondo grass, in a narrow planting strip bordered on one side by a sidewalk and on the other by the roadway. I figured that unless any of these plants were able to colonize concrete, I would be safe as long as I didn’t allow them to set seed. Whoops. All it takes is a couple of those cute little Queen Anne’s lace flowers to broadcast its progeny far and wide. The only thing that seemed to stop it more or less in its tracks from spreading into the nearby lawn was the recent flooding of the property by Hurricane Sandy: it doesn’t seem overly fond of saltwater bathing. Even so, its two thug companions seem to have gotten the worst of their salty dunking compared to the Bishops Weed. As bishops go, this plant is very far from saintly!

In fairness, what is a villain in one garden may not be quite so in another. For example I have often seen Lily of the Valley (Convallaria majalis) described as an invasive pest and yet this is the third garden in which I have been trying to get it even to attempt to establish even though I have given it the soil, moisture and light conditions which it supposedly prefers. After 10 years my original planting of a several dozen pips has just barely spread over an area approximately 2’ x 5’ wide. And in the other garden locations in which I tried it, the plantings rapidly dwindled into nothingness within the first four years. I can’t blame pests or other critters for their disappearance and can only assume that this is one of those plants that simply dislikes me personally. I will try it yet one more time in my next garden but if it still hates me then I will give it up for good.

Also in fairness, there is one member of the honeysuckle family which I suspect may not share the rampant invasiveness of its relatives – this is the winter honeysuckle, Lonicera fragrantissima, which I have had in my last two gardens.

As its name suggests, this plant has late winter flowers with the most delightful fragrance all the more welcome because of the time of year. In my Zone 7 garden and depending on temperature conditions, this is usually sometime anywhere from late February to the middle of March although in an exceptionally mild winter it has begun to bloom as early as the week before Valentine’s Day. It happens to be against a south facing house wall which I’m sure helps it along. But in any case it has not tried to take over the planting border, nor crawl underneath the siding nor invade the nearby lawn even though it does widen with age by suckering somewhat from the base. It will form a large shrub if left to its own devices but I always cut it back every April in order to neaten it up and to create denser growth with more blooms next winter. It does not have the long twining canes of most honeysuckles and so perhaps it might safely be planted among more well-behaved companions. My current shrub sits in the middle between a rose and a mock orange and thus obligingly starts off the gardening year early with a lovely scent wafting into the adjacent windows.  I would venture to say that this is the one white-hat good guy within that particular family of villains!

(Lonicera fragrantissima image from Curtis’ Botanical Magazine 1914)